Initiation of cigarette smoking is prevalent among children of current nonsmokers and it significantly increases the odds of progression to habitual smoking by late adolescence. Prevention programs are needed that are appropriate for children, designed to be implemented at home by parents, and focused on anti-smoking socialization as a tool for preventing initiation of smoking. Aim I: Design and produce an intervention that enables parents who are current nonsmokers to engage in anti-smoking socialization with their 8 year old children. The intervention will apply communication, modeling, rule setting, monitoring, guided experience, and other socialization practices to modify children's perceptions of the prevalence of smoking, the acceptability of smoking, the accessibility of cigarettes, and the personal and social consequences of smoking. Aim II: Conduct a two-group, randomized controlled trial to test the intervention. Sample: A volunteer sample of 760 male and female children from single or two-parent households who will be 8 years old and in the pre-initiation stage of smoking at baseline will enroll with a nonsmoking mother, step-mother, or other female guardian. Design: The study will follow children from ages 8 through 11 (grades 3 through 6) to measure the effects of anti-smoking socialization on smoking-related outcomes. Eligible participants who complete the baseline survey will be randomly assigned to the treatment (core program plus two annual boosters) or alternative control condition. Data on core program utilization will be obtained via telephone interviews with parents 1 month post-treatment. Data on program effects will be obtained via telephone interviews with children 12, 24, and 36 months post-baseline. Primary hypothesis: Children of current non-smokers exposed to a program of anti-smoking socialization beginning at age 8 will be significantly less likely to initiate smoking than controls by age 11. Secondary hypothesis: Among children who remain abstinent to final follow-up, those exposed to the intervention will have significantly lower susceptibility to smoking than controls. Primary analysis: Survival analysis will test the effects of antismoking socialization on initiation of smoking. Secondary analysis: A proportional odds model will test the effects of anti-smoking socialization on susceptibility to smoking among children abstinent at final follow-up.